Blog Archives

Bay Area Landscape Likely to Come Up Short on Water

Facing the difference between how much water plants need, and how much they’ll get

KQED QUEST

Scientists are looking at climatic water deficit, the water plants need but don't have.

We hear a lot about how climate change will affect rainfall in California, but climate scientists are increasingly looking at a new indicator: water deficit.

“Climatic water deficit” relates to how much water plants need to survive. “It’s the difference between what a plant would use if it had the water and what is actually available,” Alan Flint, research hydrologist with the US Geological Survey, explained on Wednesday at the North America Congress for Conservation Biology.

The value combines temperature, rainfall, the soil’s capacity to hold water and how plants use water. In agriculture, farmers irrigate their crops to make up the water deficit, but plants in the natural world aren’t so lucky. Continue reading

Dry Weather Boosts Odds of Extreme Heat

A new study finds that drought in one month increases the likelihood of heat in the next

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Sasha Khokha/KQED

As soil dries, more of the sun’s energy goes into heating the air directly, rather than evaporating moisture from the ground.

Droughts such as the one currently gripping a majority of the U.S. may dramatically increase the odds of extremely hot days, a new study found. The study, published in Proceedings of the National Academy of Sciences, explores a dynamic that is playing out right now across the country, particularly in the Great Plains, where the severe drought is priming the atmosphere in favor of an above-average number of extremely hot days.

This occurs because of feedbacks between the ground and the air: as the soil and vegetation dry, more of the sun’s energy is able to go into heating the air directly, rather than going into evaporating moisture from plants and the soil.

With drought conditions intensifying during mid-summer, the study suggests that the U.S. may be in for particularly brutal Dog Days of August. Continue reading